use node lts everywhere

Author: sivakumar-kailasam

Diff for: .travis.yml

@@ -1,5 +1,4 @@
 language: node_js
-node_js: '12'
 cache: yarn
 branches:
   only:

Diff for: package.json

@@ -73,9 +73,5 @@
 	},
 	"cacheDirectories": [
 		"tmp"
-	],
-	"volta": {
-		"node": "12.4.0",
-		"yarn": "1.16.0"
-	}
+	]
 }